Controlling an aircraft is a complex task, which requires decision-making on the basis of information provided to the pilot. Pilots may base decisions on information received from air traffic control (ATC), for example notices to airmen (NOTAMS) and automated terminal information service (ATIS) messages, or on information received from aircraft-to-aircraft communications such as (PIREP) reports. This received information may assist the pilot in determining, for example, the runway conditions on a runway upon which the aircraft is scheduled to land. Conventionally, when a liquid contaminant such as water, snow, slush, ice or oil is present on the runway, an aircraft which lands on the runway and experiences a reduced braking performance as a result of this liquid contaminant may transmit an informal comment to ATC to report reduced braking performance. ATC may then pass this informal comment onto other aircraft scheduled to land at that runway in order to warn the trailing aircraft's pilot of the reduced braking performance. In alternative scenarios, continuous friction measuring equipment (CFME) can be used to determine the surface friction of the runway and rank the braking action of the runway from “Good” through to “Poor”. However, CFME may normally be used only in a limited number of environmental conditions, and may not be effective in certain situations where the braking conditions of a runway change over a short period of time, for example immediately following a heavy rain shower on the runway. In these quickly-changing environmental weather conditions, the reporting of informal comments made by the pilot of a leading aircraft regarding the braking conditions of the runway to trailing aircraft may be relied upon more than the CFME measurements, which have an inherent lag when providing updates on runway conditions.
In another example, pilots may use received information from ATC to ensure that a trailing aircraft maintains a minimum safe separation distance to a leading aircraft. In order to maintain a minimum safe separation distance between a leading aircraft and a trailing aircraft, the pilots of the respective aircraft and/or a ground controller must recognize instances where the minimum safe separation distance between the leading and trailing aircraft is compromised, for example when one aircraft deviates from its intended flight path due to a weather phenomenon or unexpectedly increases or decreases airspeed. In those situations where the minimum safe separation distance is compromised, ATC may provide information to the trailing aircraft so the pilot of the trailing aircraft can take preventative action to regain the minimum safe separation distance, for example by throttling down in order to regain the minimum safe separation distance.
In some scenarios, for example in high workload scenarios, it is possible that the pilot of the leading aircraft may not communicate information about certain conditions to the trailing aircraft; that ATC may not communicate the information regarding the conditions experienced by the leading aircraft to the trailing aircraft fast enough for the trailing aircraft to take effective action based on the communicated information; or that a pilot may not hear a communication broadcast by ATC.
For example, if a leading aircraft experiences reduced braking performance during a landing maneuver, the pilot of the leading aircraft may not provide any informal comment about the braking action of the aircraft to ATC. If no informal comment is communicated to the trailing aircraft by ATC, the trailing aircraft may approach the landing maneuver under the assumption that the braking conditions of the runway are better than they actually are, which could lead to the trailing aircraft experiencing hydroplaning.
It is therefore desirable to improve upon conventional methods of transmitting information from a leading aircraft to a trailing aircraft. Further advantages of exemplary will be made apparent from the following description.